Disposable hot drink cups presently available may depend on insulating qualities of the material used or manner of fabrication to insulate the hand of the user from temperature of the contents or a handle may be provided to afford means to hold the cup without touching its outer walls.
As examples of the first class, mention may be made of thermoformed plastic foam and double walled cups. The insulating properties of foam are good and nestable cups made therefrom are in wide use despite the lack of a convenient handle. Cups of similar utility result from union of two cup elements, one within the other to provide an insulating air space. The latter can be prepared by thermoforming or injection molding of thin plastic to provide two similar elements, one slightly smaller than the other. The small element is placed within the larger and the upper edges are rolled outwardly together to firmly crimp the combination and provide a rounded brim pleasing to the touch.
Handles have been provided on cups of suitably treated paper by glue attachment along the side near the brim of a paper element which has unglued flanges which fold out to provide a handle. These nest very well because the handle element lies flat against the outside of the cup until folded out for use. Handled plastic cups have been made by injection molding. In order to provide enough bearing surface against the cup to be stable in use, the handle must be attached to the cup along a significant length. The length of attachment necessarily reduces nestability, resulting in undue requirement of space for shipping and storage. The length of attachment is therefore a compromise between stability on the one hand and space requirements on the other.